Preece Testing (ASTM A239)
My customer just called to ask if we can comply to A239. What does that entail?
ASTM A239 is commonly called the Preece Test. The official name is Standard Test Method for Locating the Thinnest Spot in a Zinc (Galvanized Coating on Iron or Steel Articles by the Preece Test (Copper Sulfate Dip). It is used primarily for hardware items such as nuts and bolts. It is impractical for structural steel items because of the testing solutions and handling that would be required. It has no precision because of the many possible operator techniques (Section 11.1). Compliance with A239 is technically possible. A cost of $50-100,000 for tanks, chemicals, disposal, and re-galvanizing makes samples impractical. The test destroys the coating on the tested sample.
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